French writer Simone de Beauvoir walking in a Paris street in 1971. Photograph: Georges Bendrihem/AFP/Getty Images

She was the high priestess of 20th century French thought, the mother of modern feminism and a champion of sexual freedom who shocked Paris with her threesomes and passionate bisexual affairs.

But as France begins a glittering celebration of the centenary of Simone de Beauvoir's birth next week, some academics have warned against the rush of debate and publications descending into prudish attacks on her deliberately outrageous sex life.

De Beauvoir's partnership with the philosopher Jean-Paul Sartre has been called the "original open relationship" - one of France's most celebrated and unconventional intellectual couplings. They met in 1929 and never married but devoted themselves to each other while agreeing they should be free to engage in sexual and emotional entanglements with others - as long as they shared the details.

Their long list of sometimes mutual partners included well-known intellectuals as well as some of De Beauvoir's awestruck young women students. One of them, Bianca Lamblin, later wrote a pained memoir entitled A Disgraceful Affair, telling how Sartre said before seducing her for the first time in Paris: "The hotel chambermaid will really be surprised, because I already took a girl's virginity yesterday."

Rush of interest

The hype and publishing frenzy around De Beauvoir's centenary have created a rush of interest in the relationship between a couple whom one French magazine yesterday described as the "Fred and Ginger of French existentialism".

More than a dozen books are to be published, with TV films and DVD box sets to match. De Beauvoir has a new footbridge over the Seine named after her, and the great and the good of world academia will descend on Paris for a symposium next week. A junior government minister, the urban policies secretary Fadéla Amara, even used a De Beauvoir quotation on her office's new year cards this month.

But as the latest round of De Beauvoir specials hit the French newsstands yesterday, it was clear that it is her unconventional love and sex life that would be taking centre stage.

Le Nouvel Observateur, which proclaimed a "De Beauvoir revival", featured the author's naked behind on its cover. L'Express asked if France was now finally ready to challenge an icon. Le Point marvelled at a new biography which it felt revealed a Sartre who was "sexually cold, macho, authoritarian and jealous" and De Beauvoir's traces of "authoritarianism, Pygmalion complex and calculating libertinism" that she used to "subjugate, submit and shape" those around her.

"This year, let's look at all her work together, not just the affairs and the sex - important as they are," Danièle Sallenave, the author of the De Beauvoir biography, entitled Castor de guerre, told the Guardian.

"The real game here is for De Beauvoir to step out of Sartre's shadow," she said. "I think Sartre was authoritarian, classically macho and traditional. De Beauvoir wanted to be revolutionary in everything concerning her public and private life. Sartre was ready to have parallel relations without her, behind her back, and hide it, and so behaved like a classic bourgeois husband. She wouldn't fit into that; she was much more radical."

Hazel Rowley, an Anglo-Australian writer whose recent book Tête-à-Tête detailed how De Beauvoir and Sartre's open relationship polarised public opinion, said she was worried that next week's rush of debates would see the couple described as "monsters". She said it could set off a stream of pronouncements on De Beauvoir's sex life, including "cruel, sadistic, manipulating, lying and all these stupid words".

"I don't think we should be trivialising this incredible figure by fixating on lascivious sex," Rowley said. "Why are we doing this? Are we puritanical? Do we think we're superior, and why?" She said she hoped the centenary year would "stop people mocking and belittling De Beauvoir".

More relevant than ever

Meanwhile, as President Nicolas Sarkozy this week rejected the proposed new year's honours list as too stuffy and male-dominated, politicians, actors and intellectuals alike declared that De Beauvoir's feminism was more relevant than ever in French society.

Aurélie Filippetti, a novelist and Socialist MP close to Ségolène Royal, said: "Simone de Beauvoir was the glaring proof that feminism didn't rhyme with frigidity ... She's still an inspirational figure for my generation."

Backstory

Simone de Beauvoir is best known for The Second Sex, her scandalous 1949 account of what it meant to be female - regarded as the founding text for the modern women's movement. She met Jean-Paul Sartre in Paris in 1929 when both were sitting a highly competitive postgraduate qualification in philosophy. He came first and she came second. They rejected marriage and never lived together, but within their open relationship, they agreed that their lovers would be secondary and their love for each other "absolute". Practising existentialism and individual freedom in her public and private life, De Beauvoir was an award-winning novelist, philosopher and celebrated memoirist who later championed political causes such as Algerian independence. She said her relationship with Sartre was her greatest achievement in life. She died in 1986.